Why are the aged a problem in modern society?
D000368:Aged; D001723:Birth Rate; D004641:Emigration and Immigration; D005190:Family; D005260:Female; D006801:Humans; D008297:Male; D009017:Morbidity; D009026:Mortality; D012737:Sex Factors; D012937:Social Mobility; D012940:Social Problems; D012959:Socioeconomic Factors